The summit of Ben Nevis is a large stony plateau of about 40 hectares (100 acres).[3] The highest point is marked with a large stone mound which sits an Ordnance Surveytrig point.

The ruined walls of an observatory are also on the summit. An emergency shelter has been built on top of the observatory tower for people caught out by bad weather, and, although the base of the tower is slightly lower than the true summit of the mountain, the roof of the shelter is higher than the trig point by several feet, making it the highest man-made structure in the UK. A war memorial to the dead of World War II is located next to the observatory.

On 17 May 2006, a piano that had been buried under one of the cairns on the peak was uncovered by the John Muir Trust, which owns much of the mountain.[4][5] The piano is believed to have been carried up for charity by removal men from Dundee over 20 years earlier.[6]